Sealing machine



June 9, 1953 e. R. BIDDINGER ETAL 2,641,304

SEALING'MACHINE 7 Filed March 24, 1952 2 Sheets-Sheet 1 GUY R. BIDDINGER JOHN B. HANNER INVENTOR.

yfgf ATTORNEY June 9, 1953 e. R. BIDDINGER ETAL. 2,641,304

SEALING MACHINE Filed March 24, 1952 2 Sheets-Sheet 2 FIG 2 26 3g: 27 5s 54 5 27 I3 57 s 28 1 32 lHh II zo 3| EH; 2|

GUY R. BIDDINGER JOHN B. HANNER F| 3 INVENTORS Nagy ATTORNEY Patented June 9, 1953 UNITED: STATES PATENT OFFICE GuyR. BiddingenBellwood, and-John BJ-Ianner,

Oak-Lawn,.-Ill.,zassignovs to Swift & Gnmpany,

Ghicago, 11L, a; corporation of Illinois- Application M'arc'h" 214, 1952, "SerialNo. 278264;

6 Claims.

The present invention relates to a device for sealing the thermoplastic wrapper o'fa package.

Because of commercial requirements, it is desira'ble or necessary that certain products be packaged in individual"scaledcontainersi Asone example, the growth of self-service stores has made thiemore and rnorea 'commercial'necessity in the food'fiel-d. Many of these productsare ir regularly-shaped and difficult towrap and seal by ordinary methods or without using an exorbi tantly large container.

Automatic or semi-automaticmachines have been devised to do-such packaging jobsbut, obviously', these machines will berelatively intricate andexpensive. Inord'er to justify .the substantial investment involved, itis necessar-y that the volume of produ'ct tote-handled be large. Many plants-cannotafford to purchase such machines inview oftheir'smaller outputs. Yet these same plants must put out product-in a sealed package in order to compete with others in the-market.

The principal object-f the present invention is to provide a device by-whichan-operatorcan turn out a substantial volume of attractivelywrapped and sealed packages despite the irregularityof shape that may be presentin :the object to be packaged. An advantage of the device'is that the'amount a worker can turn out is-greatly increased over what it would bel'f the operations wereconducted solelyby' hand yet the'capital'investment; involved is so I nominal' 'that the acquish tion of the device is justified b y'onlya relatively small volume plant capacity or output.

A secondobject oftheinventionis to provide a device in which theoperators' hands are not,

needed to control the action of the machine.

This leaves the operator's hands free'tohold'th'e worker could do t'he'jclbv and umo'ut satisfactory.

pa kages;

Further objects and advantages will"become There is nothing intricate in 'the'i'nvolved' 2 apparent from the following description taken 'in conjunction with the "drawings in which:-

Fig. 1 tea perspective View of an embodiment of the invention;

Fi 2 -is a'partial section taken at line 2--2"ofi Fig. 1'; and

Fig. 3 is an enlarged view of the sealing head showing the preparation of a package.

The'embodiment illustrated in Fig. 1 comprises a frame generally in; a pair of sealing jaws generally II and'lZ, a bottom sealing plate generally t3; and actuating means generally M for the jaws I I and I2. In use the actuating means M- isus'e'd to close the jaws II and: I2 about. theprojecting sides I5 of athermoplastic wrapping material 16' covering an object to be packaged, in this case a cut-up fowl Ilrestingina'cardboard'tray I 8.

Obviously, the frame may take many forms-.1

In the illustrated embodimenti's a wooden table; 20 upon which rests a metal base-plate 2 I'separated from the tabletop by an insulator 22.

IYhe jaws H and I2 are substantially identical and the structure of each will be'readily understoodfroma description of the rightehandijawwl-l which is shown insection inFig; 2'.

a longitudinal circular opening .26 therein. The

circular openings 26.accommodateelectrical heating elements made upof resistance wires 21 im-- bedded in an insulator 23. The resistance wires are connected to a sourceof electrical power in'a manner well knownin the art.

Lowerjaw 25 is fixedly mounted on base'plate- 2] andspaced therefrom by an insulator SUand a spacer-block 3]. Along the outer face of thelower jaw 25 is. a strip or hardened material 32 forming one-half of a shear to trim the ends" of the wrapping material 16 after the sealing thereof has taken place.

Upper jaw members '24 are supported from arms 34 projecting inwardly from the upper ends, of vertical rods 35'. Rods "35 slide vertically throughopenings 36inbas'e member 2! continue urged upwardly by spring -31. The extent of the upper movement is limited by pin 38 which-passes through a lower portion ofrod-31=andcontats the bottomside-of base member. Bolts Mi -slide through openings adjacent the inner end or arms H and are threaded into the upper-side of jaw members 24. About bolts 40 are'expansion springs 42 which bear against the lowerside ofarms 34 and insulator blocks 43 on top of jaw members. 24. Preferably springs .42 seat down into recesses 44in insulator. blocks 43.

An upper shear blade is welded to an angle In each .instance, there-:is an elongated upper and lower-jawmemberM and 25 respectivelmeach of whichhas' 3 46 which in turn is riveted to arm 34. As will be seen in Fig. 2, the bottom of upper jaw 24 (when hanging free) is slightly lower than the bottom of shear blade 45.

Actuating means [4 comprises a treadle 48 pivotally mounted on frame [0. The treadle 48 is connected to a crossbar 49 by means of a chain 50. Crossbar 49 is attached to an interconnecting angle 5| running at right angles thereto. Angle 5| is secured to the bottom ends of each of rods 35 so that as the treadle 48 is depressed pulling down crossbar 49, all four rods 35 are simultaneously lowered.

Bottom sealing plate l3 comprises a heating block 54 having a plurality of circular openings 55 horizontally disposed therein. Within each of openings 55 is an electrical heating element 56 similar to the heating elements described in connection with jaw members 24 and 25. Heating block 54 is attached to insulator 30.

A pan 5! overlies heating block 54 and is in contact therewith. The pan has outwardly and upwardly projecting sides 58. Preferably pan 5! extends forwardly of the sealing device to facilitate the wrapping of the packages as will hereinafter be described. In some embodiments, it will be found to be necessary to have the forwardly extending portion of the pan separately supported and insulated from the portion of the pan heated by block 54 in order that there be no softening of the thermoplastic wrapping material before it is desired that a sealing actually take place.

To operate the sealing device, the operator places a sheet of the desired thermoplastic material on the forwardly extending portion of pan 51. Such wrapping material as sheets of rubber hydrochloride, which may be purchased under the trademark Pliofilm, may be used. Tray l8 containing the product I! to be wrapped is placed on the sheet of wrapping material [6 in such a manner that the end of the wrapping material will be under tray [8 after the wrapping has been completed. The sheet of wrapping material is sufiiciently large so that it extends outwardly at either side of the tray to form projecting sides [5. Obviously, the wrapping may have been done previously and the wrapped, but unsealed, package transported to the operator of the sealing machine so that all the latter has to do is to make the seals.

The wrapped tray is then slid away from the operator and positioned so that the projecting ends [5 are centered between the open jaws H and I2. At this point, the tray rests on the sealing plate l3 which softens the end of the wrapping material l6 (which as previously mentioned is underneath the package) so that the end adheres to the remainder of the wrapper.

The operator depresses treadle 48 closing jaws H and [2 about the extending ends I5 of the wrapper. As the jaws close, the first contact with the wrapper is made by jaw members 24 and 25 which grip the wrapper and commence softening the thermoplastic material for sealing. Subsequent lowering of the supporting rods for the upper jaws 24 compresses springs 42 and displaces upper jaw members 24 with respect to arms 34. Thus, while the jaw members 24 and 25 securely grip the ends l5 of the wrapping material, the shears composed of lower shear plate 32 and upper shear plate 45 pass beside and in contact with each other to snip off the excess material beyond the point at which the 4 seal takes place. The cutting of the ends produces a neat, attractive package.

The sealing time will be dependent upon the heat applied, the material used, etc., and is a subject about which the workers in the art are thoroughly conversant. After the seal has been made, the treadle 48 is released and the wrapped and sealed package withdrawn from the machine.

Various modifications will be apparent to those skilled in the art and such modifications are deemed to be within the scope of the invention as defined by the appended claims. For example, other forms of heat generation may be used. The shears for trimming the ends of the package may be dispensed with, etc. While we prefer to seal the bottom of the package, if this is not necessary or desirable the bottom heating plate will not be needed. The description of a specific embodiment is for the purpose of complying with Section 4888 of the Revised Statutes and should not be construed as imposing unnecessary limitations upon the appended claims.

We claim:

1. A device for sealing the extending sides and end of a sheet of thermoplastic material wrapped about an object, said device including a frame, a hot plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, heating means for said plate, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member, an upper jaw member, heating means for each of said members, one of said jaw members being attached to said frame, mounting means for the other jaw member, the other jaw member being attached to said mounting means, said mounting means being supported on said frame for linear movement of said other jaw member toward and away from said one jaw member, and resilient means urging said other of said jaw members away from said one jaw member, said jaw closing means including a foot treadle to close the jaw after the wrapped object has been inserted and is being held in place by the operators hands.

2. A device for sealing the extending sides and end of a sheet of thermoplastic material wrapped about an object, said device including a frame, a hot plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, heating means for said plate, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member, an upper jaw member, heating means for each of said members, one of said jaw members being attached to said frame, mounting means for said other jaw member, the other jaw member being attached to said mounting means, said mounting means being supported on said frame for linear movement of said other jaw member toward and away from said one jaw member, and resilient means urging said other of said jaw members away from said one jaw member, said attachment of a first of said jaw members being loose to permit that jaw member to move toward and away from the second jaw member a limited distance, resilient means urging that first jaw member toward the second member, a pair of cutter blades, one of said blades being positioned.

to the other side of each of said jaw members from said plate, the blade for each jaw member being attached to the same part of the device as is the respective jaw member, said blades being positioned slightly farther apart than are the respective jaw members whereby the ends of the material will be clipped after the jaw members are brought together, said jaw closing means including a foot treadle to close the jaw after the wrapped object has been inserted and is being held in place by the operators hands.

3. A device for sealing the extending sides and end of a sheet of thermoplastic material wrapped about an object, said device including a frame, a hot plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, heating means for said plate, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member and an upper jaw member, each of said jaw members having a sealing face, being elongated in one dimension and positioned with said dimension generally parallel to the sides of said plate and with said faces parallel to each other, the lower jaw member being attached to said frame, rod means mounted in said frame for reciprocal movement along a straight line generally normal to said faces, the upper jaw member being attached to the upper end of said rod means, resilient means urging said rod means into a position at which said faces are spaced from each other, said jaw closing means being connected to said rod means.

4. A device for sealing the extending sides and end of a sheet of thermoplastic material wrapped about an object, said device including a frame, a hot plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, heating means for said plate, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member and an upper jaw member, each of said jaw members having a sealing face and positioned with said faces parallel to each other, the lower jaw member being attached to said frame, rod means mounted in said frame for reciprocal movement along a straight line at an angle with respect to said faces, said rod means being mounted in said frame in a portion thereof spaced to the other side of said lower jaw member from said plate and having an inwardly extending portion to position the upper jaw member over the lower jaw, said upper jaw member being attached to said inwardly extending portion, resilient means urging said rod means into a position at which said faces are spaced from each other, said jaw closing means being connected to said rod means.

5. A device for sealing the extending sides and end of a sheet of thermoplastic material wrapped about an object, said device including a frame, a hot plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, heating means for said plate, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member and an upper jaw member, each of said jaw members having a sealing face and positioned with said faces parallel to each other, the lower jaw member being attached to said frame, rod means mounted in said frame for reciprocal movement along a straight line, said rod means being mounted in said frame in a portion thereof spaced to the other side of said lower jaw member from said plate and having an inwardly extending portion to position the upper jaw member over the lower jaw member, said upper jaw member being attached to said inwardly extending portion, resilient means urging said rod means into a position at which said faces are spaced from each other, said attachment of a first of said jaw members being loose to permit that jaw member to move toward and away from the second jaw member a limited distance, resilient means urging said first jaw member toward said second jaw member, a pair of cutter blades, one of said blades being positioned to the other side of each of said jaw members from said plate, the blade for each jaw member being attached to the same part of the device as is the respective jaw member, said blades being positioned slightly farther apart than are the respective jaw members whereby the ends of the material will be clipped after the jaw members are brought together, said jaw closing mans being connected to said rod means.

6. A device for sealing the extending sides of a sheet of thermoplastic material wrapped about an object, said device including a frame, a plate on which said wrapped object may be placed with the end of the material against the plate, said plate being mounted on said frame, a pair of jaws to either side of said plate to seal the extending sides of the material, and means to close said jaws about said sides, each of said jaws comprising a lower jaw member and an upper jaw member, each of said jaw members having a sealing face and positioned with said faces parallel to each other, the lower jaw member being attached to said frame, rod means mounted in said frame for reciprocal movement along a straight line at an angle with respect to said faces, said rod means being mounted in said frame in a portion thereof spaced to the other side of said lower jaw member from said plate and having an inwardly extending portion to position the upper jaw member over the lower jaw, said upper jaw member being attached to said inwardly extending portion, resilient means urging said rod means into a position at which said faces are spaced from each other, said jaw closing means being connected to said rod means.

GUY R. BIDDINGER. JOHN B. HANNER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,470,852 Irwin May 24, 1949 2,496,609 Antwerpen Feb. 7, 1950 2,527,330 Prohaska Oct. 24, 1950 2,557,975 King June 26, 1951 2,591,935 Heigl Apr. 8, 1952 

